nonguix: chromium-binary: Use search-path-as-list from (guix build utils).
We rely on the upstream implementation to avoid duplicating effort.
- nonguix/build/chromium-binary-build-system (install-wrapper): Use search-path-as-list;
- nonguix/build/utils.scm (build-paths-for-input): remove variable; (build-paths-from-inputs): remove variable.